Electron-discharge device



J. H. THOMPSON ELECTRON DISCHARGE DEVICE Filed March 18, 1925 May 3, 1927.

gnuentov, FIG-3. JAMES H. THomPsoN,

wq w I am" nu mate Ma; 3, 1521. p

UNITED STATES 1,627,127 PATENT QFFICE.

nuns may :rnourson, or HOLLIDAYS covn, Wm vmenwm.

ELECTRON-DISCHARGE DEVICE.

Application fled larch 18, 1925. Serial No. 18,414.

This invention relates to an electron discharge device in the nature of an electron tube or bulb of the character commonly employed for various purposes, such as detecting, transmittin and amplifying electric signals; particu arly in the art of wireless telegraphy and telephony.

The device of the present invention has features in common with the construction illustrated in my copending applicatlon, Se-

rial Number 750,340, filed Nov, 17, 1924. However the parts are arranged in a dlfi'erent relation and in such manner as to msure economy in construction, readiness of e- 1 pair and maximum efliciency 1n operatlon. Another object of constructing the device as illustrated 1n this application, is to remove obstruction from the path of-the electron and to eliminate eddy currents in the electron stream from the cathode to anode.

A further object of the inventionis to reduce self-capacity in the seals to 9. mmmum. In the construction herein shown and described, the electrode and anode conductors are widely separated.

Further objects and advanta es of the invention will be set forth in t edetailed' descri tion which follows:

In t e accompanying drawing Fig. 1 1s a side elevation constructed in accordance with the invention, with arts broken away.

Fig. 2 is a plan view t ereof.

gig. 3 is a fragmentary perspective Fig. 4 is an underside plan view of the base of the bulb illustrating the relation of the several terminals.

Like numerals designate corresponding parts in all of the figures of the draw ng.

Referring to the drawing, 5 designates the bulb and 6 the base or stem of the bulb, these parts being of well known design. The shape of the bulb makes no difierence and I contemplate employing a bulb of any suitable size or shape. Sealed into the stem of the bulb are two upstanding filament supview,

porting posts 7 and 8. Those ortionsof the posts which lie within the 'ulb 5, are of concave-convex form in horizontal section, and have their concaved faces disposed outwardly. Each ost carries four ointed ears 7", 7", 7 and respectively. e up per pairs of cars are spaced from the lower airs of ears by the re atively deep notches i and 8', the presence of WhlCh insures ample clearance for the controlling electrode porting posts 7 and 8. These screws are.

preferably provided with slots'12 upon their lnner en s so that they may be turned from the inner or concave faces of the posts. this arrangement permits the approach of a screw-driver from such an angle as to facilitate the manipulation of the screws without danger of damage to adjacent parts. However it is to be understood that the headsof the screws may 'be slotted in the usual way so that they may be mani ulated from either side, and I have so in icated them. Plates 14 and 15 are supported on posts 16 and 17 sealed in the base 6, and said plates are preferably tied togetherat their upper portions by a strap or bar 18. In Flg. 4 I have illustrated the usual four contact studs, two of which are marked with the letter F (indicating filament), one with the letter G (indicating grid), and one with the letter P (indicating plate). The studs marked F are in electrical communication through conductors indicated at 20 and 21, with the lower ends of the posts 7 and 8. The stud marked G is connected to the id conductor '9, from which the brane es 9 and 9 extend. The stud marked P is in electrical communication throu h a conductor indicated at 24 with oneo the plate supporting posts.

I contemplate making the cathode or filament of any suitable refractory material such, for example, as tungsten.. In my copending application above referred to, the anode (plates are shown as being corrugated to len rigidity to them and it is manifest that said construction ma be employed in the present case, if desired.

Since the strands of the controlling electrode and strands constituting the filament, are in substantial parallelism, there is no tendency for eddy currents to be set up. All of the parts have such clearance with respect to each other that there is no obstruct1on whatever to the free flow of the elec trons, with the result that a tube of maximum efliciency is produced.

It is to be unde stood h the nv n is not limited to the precise construction set forth, but that it includes within its purview whatever changes fairly come Within the terms or the spirit of the appended character described comprisin a pair of filament supporting posts, both 1n spaced relation to each other, with a pair of independent strands extending therebetween on each side thereof and in vertically spaced relation to each other and removably secured at their ends to said posts; a grid electrode extending around said posts at a level to bring it between the upper and lower strands of the pair of filaments where it lies in substantial parallelism with said filaments, and anode plates disposed outwardly of the grid electrode and supports for said anode lates.

2. A tube 0 the character descri d comprising a supporting base, a pair of posts extendlng therefrom and in s aced relation to each other, said s eac having two airs of ears, the pairs of ears on each 0st ,ing vertically spaced from each 0t er,

along the opposite sides of each of the posts and 1n substantial parallelism with the filaments, and anode plates disposed outwardly 35 of the grid electrode.

In testimony whereof I afiix my signature.

JAMES HENRY THOMPSON. 

